Better Ways To Stop Your Car Without Spending Big Bucks

Possible Cause: Improper Pedal And Pushrod GeometryWith the pedal fully depressed the angle between the master cylinder and its pushrod must NEVER be less than 90 degrees (see Pushrod Geometry illustration below). If the angle falls to just 1 degree less than 90, brake pressure will decrease suddenly and dramatically. This condition is described as the pedal/pushrod assembly's being "over center."

Solution: Check And Correct The AngleUse a small carpenter's or machinist's square to check that when the pedal is fully depressed, the effective angle between the pushrod and the pedal is never less than 90 degrees. If a visual check is not possible, measure the pressure at the caliper and look for a condition where pressure initially builds and then suddenly falls as the pedal is depressed farther. In some cases, lengthening the pushrod may alleviate this condition or it may be necessary to relocate some components to achieve the proper pedal geometry.

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The Master Power Hydraulic Pressure Tester (PN AC2004, $89.95) includes a 1,000-psi, liquid-filled gauge and adapters to fit most brake lines. Low pressure at only one location usually means a pinched or blocked line. Low pressure at all four corners means you need a new master cylinder or a higher pedal ratio.

Special Note: When using a master cylinder that's too big (unfortunately, an all-too-common practice), it's possible that pedal travel may be reduced enough to hide an over-center condition. Then, when the master cylinder is replaced, the pedal movement is increased and an over-center problem becomes evident.

Problem: Extreme Brake Pedal EffortThe vehicle has a firm pedal, but it takes a great effort and serious leg muscles to get the car to stop.

Possible Cause 1: Improper Caliper To Master Cylinder RatioA simple hydraulic rule: When Volume Goes Up, Pressure Goes Down and vice versa. You must select a master cylinder that will provide the proper volume to actuate the system, while still delivering the correct pressure. A large-bore master cylinder will move more fluid but at a lower pressure. A small-bore master cylinder will create higher pressure but can't move as much fluid per stroke.

Stainless Steel Bakes offers this adjustable proportioning valve to tell you just how much pressure you're putting into your rear brakes. To be able to read it while driving, however, is up to you to figure out.

Possible Cause 2: Engine Vacuum Too LowMost vacuum boosters will produce good results only if at least 16-18 inches are available at idle.

Solution 2: Increase VacuumIt is sometimes possible to make minor adjustments to the engine to maximize idle vacuum, but engines with even moderate performance camshafts can produce too little vacuum. In some cases it's possible to employ a master cylinder with slightly less piston area to give the system more pressure. Other alternatives include removing the vacuum booster and reconfiguring the pedal geometry for manual operation or converting to a "Hydra Boost" system (hydraulic booster driven off a pump, such as a power steering unit) or installing an electric vacuum pump, which is available from Master Power.

Possible Cause 3: Pedal Ratio IncorrectThe brake pedal ratio is determined by dividing the distance from the center of the pedal pivot to the center of the pedal pad in a straight line-see "Pedal Ratio" illustration. (Note: Most brake pedals are curved but do not calculate the curve).

The Master Power Hydraulic Pressure Tester (PN AC2004, $89.95) includes a 1,000-psi, liquid-filled gauge and adapters to fit most brake lines. Low pressure at only one location usually means a pinched or blocked line. Low pressure at all four corners means you need a new master cylinder or a higher pedal ratio.

Stainless Steel Bakes offers this adjustable proportioning valve to tell you just how much pressure you're putting into your rear brakes. To be able to read it while driving, however, is up to you to figure out.

Electric vacuum pumps like this one from Master Power can be the cure for a hard pedal if you've got power brakes and a big cam.

Performance Friction's Z-Rated hi-temp brake fluid is great for street and occasional track use. For racing, Baer recommends Castrol SRF fluid. Both these fluids come packaged in metal cans because plastic bottles are porous and will allow moisture to seep into the fluid.

No matter how hard you try, you can't build the best brake system without bending some lines. And what you bend you must also flare, and there's no better brakeline flaring kit available than this one from Master Power.

An "over-center" brake pedal/pushrod combination will kill brake pressure under hard use. Master Power offers this universal adjustable pushrod assembly to help cure that problem.

Want your money to go along way and have your brakes stop at a shorter distance, there many solutions and one includes getting a brake system from Wilwood, Baer Brakes, Master Power, or Stainless Steel Brakes - Super Chevy Magazine » Read More